PortSensor is a simple but powerful server monitoring tool. Sensors can be created to monitor nearly any TCP/UDP service, including: HTTP, FTP, POP3, SMTP, DNS and most popular database platforms (MySQL, Oracle, PostgreSQL, SQL Server, etc). In addition to standard services, custom sensors can be created using SSH/SNMP to monitor other critical server metrics, for example: processor loads, mail queue loads, disk space usage, database queries per second, log activity and more.